Last week, in writing about President Obama's decision to take a more hands-on approach to his Nuclear Posture Review, I implied that Secretary of State Hillary Clinton used a public speech to throw a dart at the Defense Department and Secretary Robert Gates by attempting to redefine what it means for the U.S. to be confident in the nuclear stockpile it has.

I quoted Clinton as saying that "General [Kevin P.] Chilton, Commander of U.S. Stratcom, has said repeatedly that he doesn't need new nuclear weapons capabilities -- but he must be confident in the capabilities that we have."

A senior defense official called to dispute the view that Clinton's comment amounted to a challenge to the Pentagon.

"What Chilton said accurately reflects where Secretary Gates is and the rest of the military is, which is that the arsenal we do have needs to be tended to, so that we can assure our allies and our adversaries that our stockpile has the capabilities that we say it has," the official said.

In 2008, Gates told an audience that "there is absolutely no way we can maintain a credible deterrent and reduce the number of weapons in our stockpile without either resorting to testing our stockpile or pursuing a modernization program."

The defense official, an administration official and a State Department official, all speaking on the condition of anonymity because the deliberations are supposed to be private, agreed that the interagency process to produce a new nuclear posture review is proceeding apace  without exposing grand fissures between the DoD, the State Department and the White House.

That doesn't mean there aren't any fissures.

In Gates's 2008 speech, which the defense official said was consistent with his current view,  Gates said it would become impossible to "keep extending the life of our arsenal -- especially in light of our testing moratorium. It also makes it harder to reduce existing stockpiles, because eventually we won't have as much confidence in the efficacy of the weapons we do have."

Extending the life of the current arsenal means refinements to the nuclear cones, to the  warheads themselves, and to the delivery systems. Vacuum tubes need to be replaced on some of the warheads, and advanced safety and surety features need to be added, Pentagon officials have said. Right now, the Department of Energy is working to update missiles through its Life Extension Program, or LEP. Experts seem to be divided about whether the LEP enhancements change the capabilities of the missiles. And arms control advocates say the vacuum tube argument is a red herring; the tubes are used on radar fuses, not on the warheads, and remain in working order.

Gates wants the Nuclear Posture Review to include funding to study designs for new nuclear warheads.

To others, including some in the State Department, the NPR should include nothing of the sort.

Senior Obama administration officials hold the latter view.

That follows the president's commitment to maintain a deterrence while pursuing an aggressive strategy of reduction. There ought not be any forward leaning into the next generation of nuclear weapons, Obama believes, because the current generation is sufficient for now -- and forever.

The Defense Department faces a PR challenge.

True -- the warheads tend to be old, haven't been tested in more than a decade, and, in some cases, have exceeded their projected viability. Secretary Gates and the Department of Energy under President Bush asked Congress to fund what it called the Reliable Replacement Warhead program, which would have replaced most of the current stockpile with new, more efficient weapons that would have allowed the number of missiles to be reduced. Congress balked. The view of then-Senator Joe Biden was that the science wasn't there, the program reeked of Bush-Cheney imperialism, and it would be needlessly provocative.

The defense official acknowledged the RRW program was "terribly marketed."

"The impression was left that we were trying to build new nuclear weapons, and that's not what we wanted to do," the official said.

So -- "Can you find a way to sell the idea of new warheads and new weapons without there being a new nuclear capability?" the senior defense official said. "Obviously, that's an expensive proposition. But it's extraordinarily costly to continue to tinker with the weapons that we do have."

Ellen Tauscher, the undersecretary of state for arms control, is firmly against a new weapon design.

"I think there are a lot of people that still hope for the return of RRW, and they are going to be sadly disappointed," she told the Cable.

For Tauscher, stockpile management means refurbishment -- and nothing new. You can't build a new warhead without enhancing capability, she believes. And there's no evidence to suggest that, with a few modifications, the current stockpile wouldn't be viable for years to come.

The battle lines are drawn.

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